Are your kids' closets ready for cooler temps? No? With snow already falling in some parts of the country and near-freezing nighttime temperatures being recorded, now is the perfect time to give your boys and girls jackets that will last them all winter long.

Like adult gear, kids' outerwear comes with its own lingo that can quickly get muddled – making it easy to buy more (or less) jacket than is really necessary. Here's a primer to help you get just what they need.

Down insulation. Down is made up of fine, fluffy goose or duck feathers. It's lightweight and warm – and works efficiently (just like Mother Nature designed it to). Although down is most commonly found in jackets, it can sometimes be seen in other outerwear, like snow pants, hats and gloves.

Pros: Ounce-for-ounce, it's warmer than synthetic and has a high warmth-to-weight ratio.

Cons: Loses its insulating properties when it's wet, is slow to dry, and usually requires special cleaning.

Pros: Provides insulation even when wet, dries quickly and is generally less expensive than down.

Cons: Bulkier, breaks down over time, degrades faster than down.

Fill power. Down outerwear is usually graded by fill power – and tells you how many ounces of down you'll find in a cubic inch. The higher the number, the better the jacket's insulating ability. Some synthetic jackets' insulation is described similarly (i.e. equivalent to 500 down fill power); that way you can easily compare jackets. Alternately, synthetic jackets are sometimes rated as effective to a specific temperature.

Hard shell. Think of this as a waterproof windbreaker with no insulation. Depending on your kids' jackets, they may be able to zip their insulated jacket into a hard shell or can layer them while skiing or playing in the snow.

Soft shell. Like a hard shell, these girls' and boys' jackets are great for snow, but they're usually only water-resistant instead of waterproof. They're also generally insulated, but can be layered for super-cold conditions.

In addition to kids' outerwear that's rugged and warm, some companies even offer jackets with adjustable sleeve lengths (and snow pants with adjustable hems) that make it easy for growing kids to use one coat all winter long – and look good while they're at it.